1. Field of the Invention
This invention relates to electrical connectors and more particularly to electrical connectors of the type used in the medical industry to transmit physiological data to a monitoring instrument.
2. Description of the Prior Art
With the introduction of electronic monitoring instruments into the medical profession a demand was created for devices which could easily connect the remote monitoring instrument to the physiological signal producing electrodes attached to the patient. In response to this demand, a multitude of electrical connectors of diverse types have been developed. One type of the aforementioned connectors connects the monitoring instrument to the patient by snapping onto the electrode. These connectors are pressed onto the electrode and snappingly clipped onto a reduced neck portion of the electrode.
A second type of connector provided for the clipping onto the electrode by the use of a scissor motion and is best represented by the Lopin U.S. Pat. No. 3,774,143. The Lopin electrical adaptor consists of a conducting wire formed so as to have a pair of parallel opposing jaws which are contained within a pair of arms having a biasing hinge therebetween. In addition to the foregoing, the Lopin electrical connector has a cap which fits into the handle assembly to protect the conductor wire. The connectors such as Lopin are connected to the electrodes by squeezing the arms together against the bias of the hinge which in turn opens the jaws to allow the electrode to pass through. The handles are then released causing the jaws to contract and clasp the electrode.
In manufacture and use, the above connectors have various shortcomings. The snap-on connector requires a downward force against the electrode and ultimately the patient to snap the connector thereon. This downward force can result in patient discomfort and possibly electrode damage. Furthermore, the snap-on connector can not be easily removed from the electrode without pulling the electrode away from the body of the patient. The hinge connector such as Lopin requires numerous manufacturing steps to construct which add to the cost of the connector. These manufacturing steps include the bending of the conductor wire, soldering the cable end to the conductor wire, embedding the above into the arm structure of the connector, molding the cap and connecting the cap to the arm structure. Another drawback of the Lopin electrical adaptor is that its structure may interfere with the pivoting of the connector about the electrode which is often necessary for the proper placement of the cables. Under certain conditions, i.e., a large electrode or the operation of the connector in a wet environment, the electrode in the opposing jaws of Lopin may migrate so as to abut the sides of the bore which holds the jaws. This would result in the electrode being contacted by not only the jaws but also by the bore surface. The bore surface-electrode contact increases the friction between the connector and the electrode thereby hindering the pivoting of the connector about the electrode.
It is a primary object of the present invention to provide an electrical connector-electrode assembly that overcomes the problems noted in the prior art above.